Most animal cells have the ability of secreting cell-derived extracellular vesicles of various sizes and compositions. These extracellular vesicles are found in all biological fluids, including blood, urine, saliva and cultured medium of cell cultures (Loyer X, Vion A C, Tedgui A, Boulanger C M. Microvesicles as cell-cell messengers in cardiovascular diseases. Circ Res 2014; 114: 345-53; Ohno S, Ishikawa A, Kuroda M. Roles of exosomes and microvesicles in disease pathogenesis. Adv Drug Deliv Rev 2013; 65: 398-401).
Extracellular vesicles are membrane structure vesicles with diameters from about 20 nm to about 5 μm. They differ in sizes and compositions and include various species such as exosomes (about 30-100 nm), ectosomes, microvesicles (about 100-1,000 nm), microparticles, etc.
The different types of the extracellular vesicles are distinguished based on their origin, diameter, density in sucrose, shape, precipitation rate, lipid composition, protein marker, secretion type (i.e., whether they are induced by signals or naturally produced), etc. For example, microvesicles are membrane vesicles ranging from about 100 to 1,000 nm with irregular shapes. They originate from the plasma membrane and are known to contain integrins, selectins, markers including CD40 ligand, and lipids including phosphatidylserines. And, exosomes are the smallest membrane vesicles ranging from about 30 to 100 nm (<200 nm) with a cups shape. They originate from endosomes and are known to contain tetraspanins such as CD63 and CD9, markers including TSG101 and ESCRT, and lipids including cholesterols, sphingomyelins, ceram ides and phosphatidylserines.
The extracellular vesicles reflect the state of the cells (donor cells) from which they are secreted, exhibit various biological activities depending on the cells from which they are secreted, and play an important role in cell-to-cell interactions as they transfer genetic materials and proteins between cells.
In plants too, small vesicles are released to the extracellular space as a result of fusion between the plasma membrane and multivesicular bodies, and vesicles in multivesicular bodies are observed in the extracellular space of plant cells of various species (Marchant R, Peat A, Banbury G H. The ultrastructural basis of hyphal growth. New Phytol. 1967; 66: 623-629; Halperin W, Jensen W A. Ultrastructural changes during growth and embryogenesis in carrot cell cultures. J Ultrastruct Res. 1967; 18: 428-443; Marchant R, Robards A W. Membrane systems associated with the plasmalemma of plant cells. Ann Bot. 1968; 32: 457-471). Also, it was recently reported that the exosome-like nanoparticles derived from plant cells are similar to the exosomes derived from mammalian cells in nanosized vesicular structure and nanoparticle composition (An, Q, Hückelhoven, R, Kogel, K H and van Bel, A J (2006). Multivesicular bodies participate in a cell wall-associated defence response in barley leaves attacked by the pathogenic powdery mildew fungus. Cell Microbiol 8: 1009-1019; Regente, M, Pinedo, M, Elizalde, M and de la Canal, L (2012). Apoplastic exosome-like vesicles: a new way of protein secretion in plants? Plant Signal Behav 7: 544-546).
Exosomes have been used mainly as biomarkers. However, technologies for using exosomes for specific purposes based on the intrinsic efficacy of the exosomes have not been developed. In particular, little is known about the specific use of exosome-like membrane structure vesicles derived from plant cells. As for ginseng, although the skin whitening effect of ginseng-derived extracts or ingredients thereof has been reported, the skin whitening effect of ginseng-derived exosome-like membrane structure vesicles has not been reported. The prior art about ginseng extracts is disclosed in Korean Patent Publication No. 10-2009-0130801.